![Sample our Physical Sciences journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/110819/TOC-Subject-Sample-2021-Physical-Sciences.jpg"})
ABSTRACT
A 1% Y and 1% Mn alternately doped nonstoichiometric (Ba0.6Sr0.4)0.8TiO3 (Y/Mn-BST) film was attempted to design and prepare by an improved sol-gel method on Pt/Ti/SiO2/Si substrates, and its ultralow dielectric loss with other dielectric properties was studied in this paper. Undoped, Y doped and Mn doped BST films were also compared. All films grow along (110) orientation and show polycrystalline cubic ABO3 perovskite structures. Pure film shows the weakest crystallization, while Y/Mn-BST film exhibits the strongest crystallization. Superfluous Ti acted as Ti doping makes B sites so saturated that superfluous Ti4+ ions have to enter A sites and first replace Sr2+ ions and then replace Ba2+ ions to show donor doping, thus result in the smallest lattice parameter and decreased Ba/Sr ratio. Doped Y3+ or Mn2+ ions only enter A sites and replace Ti4+ ions to reveal acceptor doping, and thuscause lattice parameters and Ba/Sr ratio a little larger than the undoped BST film. The Y/Mn-BST film shows the largest lattice parameter and increased Ba/Sr ratio with acceptor doping. Each nonstoichiometric BST film show smaller capacitance, tunability and dielectric loss than normal BST film, but the Y/Mn-BST film reveals better combination of dielectric properties in particular much smaller dielectric losses of 0.0051∼0.0067, thus show more obvious practicability and reliability in tunable microwave applications.
Funding
The paper is supported by the National Natural Science Foundation of China of 51172034, 61301052 and 61474016, the field of equipment development fundof 61409220110, the National Defense Science and technology innovation special zone project of 17-163-13-ZT-009-125-001, the International cooperation project of Sichuan Provincial Department of science and technology (2017HH0067), and the Sichuan science and technology support projects of 2017GZ0105.